It's an item so has no tense
Did not do it -> did not do it (same past tense form)
"Returned" is already in the past tense form.
Doubled is already the past tense form of double.
Arrived is already in past tense. It is the past-tense form of the word arrive.
Found is already past tense. The present tense form is "find."
That is already in past tense form of the verb think :)
Sailed is already the past tense form of 'sail'.
Past tense is a tense that was already done, or it takes the plural form. Present tense is a tense that was a singular.
Listened is already in past participle form. It is the past tense and past participle of listen.
That is already in past tense form of the word think. The future tense of think is will think. or as I said "thoughted"
Already is not a verb and does not have a past tense.
"Past tense" is a grammatical term used to refer to the form of a verb that indicates that something has already happened or been completed. It is a verb tense that is used to show actions that have already taken place in the past.